Power operated tool attachment for electric drills and the like



March 5, 1957 T. B. KEESLING T 2,

POWER OPERATED TOOL. ATTACHMENT FOR ELECTRIC DRILLS AND THE LIKE;

Filed Feb. 24, 1954 T 35a FIG-.3. 13

22 a 576 70 1a 3235 3% 3 a; 24 1F 5 21 k w t" ig 3.9a

lNVENTO/Q mow/A: BKEL'SL/A/G BY 14 .QM Arm/away United t res Patent vPOWER OPERATED TGOL ATTACHMENT FOR ELECTRIC DRILLS AND THE LIKE ThomasB. Kees ling, Los Gatos, Calif., assignor of onehalf to C. H. Keesling,San Jose, Calif.

Application February 24,1954, Serial No. 412,359

Claims. (Cl. 143-68) .The present invention relates to power-operatedreciprocating tools, such as saws, and is concerned more particularlywith a power operated tool attachment for drive means such as anelectric drill, which can be manually controlled in application to thework.

This application is a continuation in part of my copending applicationSerial No. 323,370, filed December 1,. 1952.

It is the general object of the invention to provide a power operatedsaw attachment of the above character of improved construction andeconomical design.

It is a still further object of the invention to provide a poweroperated attachment of the above character hav ing improved means forshielding the working parts from particles.

Other objects and advantages of the invention will be apparent from thefollowing description of a preferred embodimentthereof, as illustratedin the accompanying drawings, in which:

Figure 1 is an elevational view of the saw.

Fig. 2 is a sectional view taken on the line 22 in Figure 1.

Figure 3 is an elevational view-of the saw with the cover portion of thebody removed.

Figure 4 isjasectional view taken in a plane indicated by the line 4-4in Figure 2. 1

Figure 5 is an end elevational view taken in a plane indicated by theline 5-5 in Figure 2.

Figure 6 is a fragmentary elevational view of the cover-V I r.

Figure 7 is aperspective view of the saw clamping head shown'in explodedfashion.

Figure 8 is an elevational view of the dirt shield.

Figure 9 is a sectional view taken on the line 9-9 in Figure 8.

Figure 10 is a fragmentary sectional view illustrating a modified formof dirt shield. I

The power-operated hand-controlled tool ofthe instant inventioncomprises a body including a body 10 and a cover 11 both of die'castconstruction whose parting line lies in a plane parallel to certainworking parts of the tool including a reciprocating drive link 12. Thecover 11 (Figures 2 and 6) is provided about its periphery-with a flatsurface 16'which engages flush with a corresponding peripheral edgesurface 17 of the body 10. The cover 11 is also provided with aninwardly spaced outwardly projecting rib 18 which seats within arecessed portion 19 of the body in flush engagement with the side wall21 adjacent the flat peripheral edge portion 17. As seen in Figure 6,the front end portions of the rib 18 of the cover 11 merge with abearing pad 36 for the reciprocating elements of the tool. The cover 11is provided with four threaded apertures 22 to receive the threaded endsof a socket cap screws 23 seated in corresponding aligned apertures 24of the base 10.

The body 10 (Figure 2) is provided with a boss or extension 26 tojournal internally threaded drive thimble I 2,783,790 Patented Mar, 5,1957 I 2 end face of boss 26. The other end face of boss 26 is engagedby a drive disc 28 secured to and against the end of thimble 27 by athreaded extension 28a. A chucking shaft 30 is threaded into the thimble27 and is provided with a hexagonal collar 30a for engaging the thimble27. The driver or disc 28 carries an eccentric drive pin 31 by which itis pivoted to the rearward end of the drive link 12. The drive link 12is guided by an integral pad of bearing portion or pad 36 at its frontend, where it is connected by a pivot pin 33 carried in a slide 34. Theslide 34 is mounted for longitudinal movement in a track formed by side.walls 35 of the body, is supported at its lower side by walls 35aadjacent sidewalls 35 and by a pad 37 of the body 10. The slide 34 isengaged by the side guide flanges 39a of a channel-shaped, clamping head39 of sheet metal construction, which flanges are also guided in therespective guide walls 41 of the body 10. As seen in Figures 3 and 7,the top wall of the head 39 has a concave recess to provide clearancefor the link 12, and the side flanges 39a extend rearwardly inoverlapping relation therewith. The head 39 has its upper surfaceengaged with the pad 36 which also guides the link 12 at its forwardend. The front edges of the head 39 are made sharp and close-fitting forcleaning out of metal chips and other particles. The head 39 has as apart of its structure an insert plate or spacer 42 which is interposedbetween the head and the saw blade 47 when the blade is clamped inplace. This plate 42 has a suitable central aperture to engage over thecounters sunk portion of the head and is notched to engage a downwardlyformed ear 3% of the head, the ear 39b and the cooperating notch forminginterlocking portions to maintain the position of the parts. Byemploying plates 42 of suitable thickness tools of differing thicknesscan be secured in place in the head.

The head 39 (Figures 2, 4 and 7) forms a part of the saw securing meansor clamp and for this purpose has a countersunk recess receiving aclamping screw 46 threaded into the slide 34. Clearance for the end ofscrew 46 is provided by a recess 38 in pad or surface 37. The saw 47 isclamped between spacer plate 42 of the head 39 and the slide 34, the sawhaving a longitudinal slot47a which enables endwise positioning of thesaw over the screw 46. The molded recess 48 of the cover provides foraccess to the screw 46 in the extended positionof the saw as seen inFigure 2. The straight side edges 47b engage the inner surfaces of theside flanges 39a of the head 39. The shoe 51 forms a work guide orwork-engaging piece and is formed with a front edge 51a which isperpendicular to the path of movement of the slide 34 and the head 39and end portions 51b bent to form an included angle of less than degreesThe saw blade 47 is" thus mounted for a'straight line movement-withtheslide 34 having its edges confined by the side flanges 39a of thehead as seen in Figure 4 so that the saw is definitely located in placeand is securely held in performing the work.

Referring to Figures 1, 2, 3, 8 and 9, a dust or dirt shield 56 is shownwhich is interposed between the teeth of the saw blade 47 and the head39 and the slide 34. The shield 56 is preferably formed of a resilientflexible material such as synthetic rubber and is provided with acentral slit 57 to engage closely over the saw, this slit 57 mergingwith inclined recessed walls 58a opening to ward the operating parts forthe saw including the slide 34 and the head 39. The shield 56 is alsoprovided with 27 having a hexagonal flange portion 27a engaging oneapertures 58 which engage over the two ends of the shoe 51 to secure theshield in place stretched across the end of "the saw attachment. As seenin Figure "3, for example with the slide 34 projected the shield 56 isstretched slightly, so that as the slide .34 and the head.39.reciprocare, they vibrate the shield to dislodge particles resulting from thesawing operation from the .face thereof. The slit 57 engages closelyover blade 47 and tends to open as the blade moves outwardly and toclose as it moves inwardly. The tendency of the lips to flex and graspthe blade as it moves inwardly 'is enhanced by the recessed constructionprovided by the beveled walls 58.2, which extend through .a majorportion of the thickness so as to provide thin lips.

In Figure 10 there is shown a modified form of shield 59 havingoutwardly projecting taperedlips 59a defining the slit engaging the sawblade. The shield 59 also has tapering molded side walls 59b aroundits-entire periphery for engagir walls of the body 10 and the cover 11.The recess 3 is only partially .covered by the wall 5912 so that accesscan be had to the screw 46. The shield '59 is secured on the sawattachment in thesame manner as the shield 56 and functions inthe samemanner with respect to the saw blade.

Referring to Figures 1 and 3 it is seen .thatthe body and cover formtogether concave hand grip portions 53 whereby the tool may be grippedin onehand and the other hand can carry the handle of a power drill withwhich it is used. If it is used with a fiexibleshaft drive,

both hands may be employed in holding the tool with respect to the work.

While 1 have shown and-described a preferred embodiment of theinvention,'it will be understood that the invention is capable ofvariations and modification from the particular form shown, so that itsscope should be lim ited only by the scope of the claims appendedhereto.

1 claim:

1. In an attachment for a portable electric drill and the like, a bodystructure of elongated longitudinal shape forming a hand grip, said bodystructure having an apertured boss disposed transverse to the directionof elongation thereof, guide means extending longitudinally of said bodystructure, a reciprocatory slide mounted in said guide means, means fordetachably securing a working tool to said slide, and means foroperating said slide including a chucking shaft journalled in said boss,said chucking shaft providing for connection to an electric drill, andalso providing a pivot axis about which said body structure can befreely rotatively adjusted during use of the attachment.

2. In an attachment for a portable electric drill, a body of elongatedshape having an apertured boss disposed transverse to the direction ofelongation and also having guide means extending longitudinally thereof,a cover for said body. having pad portions opposed to the guide means ofsaid body, means for securing the cover on the body, operating means insaid body including a chucking shaft journalled in said boss and a slidedriven by said shaft, said shaft providing a pivot axis for saidattachment, 2. tool, a tool clamping head releasably secured to saidslide, said head being channel-shaped and having guide portions, eachguide portion engaging freely over an edge of the slide on one side andslidably engaging the guide means in the body on the other, and se.curing means extending through said head and said slide and clamping thetool therebetween.

3. In an attachment for a portable electric drill, a body of elongatedlongitudinal shape forming a hand grip and having a boss transverse tothe direction of elongation, said body also having integrally formedguide means extending longitudinally thereof, a cover for said body andsimilarly elongated, and said cover having pad portions opposed to theguide means of said body, 'a reciprocatory slide mounted in'the guidemeans of said body and engaged by said pad portions, drive means in Saidboss for said slide including a chucking shaft, and means for detachablysecuring a 'Workingtool to said slide, said chucking shaft providing forconnection to an electric drill, and also providing a pivot axis aboutwhich said body structure can be freely rotatively adjusted during useof the attachment.

4. In an attachment for a portable electric drill a body of elongatedlongitudinalshape having a boss transverse to the direction .ofelongation, a cover for said body similarly elongated, saidbody and said:cover being symmetrical with respect to a longitudinal plane disposedcentrally thereof'and parallel to the axis of said boss to form a handgrip, a reciprocatory slide mounted in said body for reciprocationlongitudinally of said body, drive means for said slide including achucking shaft-mounted in said boss having a drive connection to saidslide, and means for detachably securing a working tool to said slide,said chucking shaft providing for connection to .an electric drill, andalso providing a pivot axis about which said body structurecan be freelyrotatively adjusted during use of the attachment.

5. A tool attachment as recited in claim 1 in which said securing meansincludes a channel shaped clamping head to receive the tool, a spacerplate received within the head for clamping engagement with the tool,and se- References (Jited in the file of this'patent UNITED STATESPATENTS 938,680 Martin Nov. 2, 1909 1,116,640 Sporleder Nov. 10, 19141,322,873 Brull Nov. 25, 1919 1,569,301 Reed Jan. 12,1926 1,679,884Thomas Aug. '7, 1928 1,698,788 Gibson Jan. 15., 1929 1,793,053 Cahill etal. Feb. 17, ,1931 1,826,188 Pickering et al'. Oct. .6, 1931 2,143,981Harding Jan. '17, 1939 2,146,777 Strong Feb. 14, 1939 2,452,148 RhodesOct. 26, 1948 2,619,132 Pierce Nov. 25, 1952 2,668,567 Olson Feb. 9,1954 FOREIGN PATENTS 208,301 Switzerland .Apr. 16, 1940 916,733 FranceAug. 26, 1946 and...

